Is it not shifting into 3rd gear or OD? They are designed to not shift into OD until the transmission fluid warms up, this is normal.

 

SuperchargedMR2 is correct, if it's OD you're actually talking about. Another over-engineered aspect of the Previa to protect itself. But if it's now going into 3rd gear then that could be an issue.

 

Not necessary, If I recall the Cressida had an electronic auto tranny that would stay in 2nd while cold, then would move up to 3rd and OD as the coolant warmed and was finally at operating temp. The owners manual even stated the top speed in 2nd for the auto tranny was over 55 MPH.

 

When the coolant temp is below 140 degrees (F) it will not shift into overdrive. As soon as your temp hits 140, it will shift. This is all programmed in the ECU. If you really think it is messed up I would check your coolant temp sensor.

 

If you have your owners manual, available, look there. There should be a section on the auto tranny and how it shifts/works You may/should see a phrase that the tranny won't shift up to a certain gear if the coolant is not at a certain temp.

 

thanks for the ideas

thanks for the ideas. I'm not sure if it's not going into overdrive or third gear. I am assuming that when it starts from stop it goes into first gear, then as you drive you can feel a shift into the next gear (2nd gear, I assume). Then as you gain speed in 2nd gear you can feel that it should be shifting but it doesn't but just stays in 2nd geqr. Eventually it does shift to the next gear and the problem is over for this time. (This is what it does on flat ground.)

When it climbs the hill near our house, it will go from 1st to 2nd but then,still climbing the hill, it again will feel like it should be shifting and if you keep giving it more gas it will kind of start to shift but then quickly kind of change its mind and jump back into the same gear it was already in (2nd) but still feel like it wants to change to a higher gear. Somtimes it will repeat that manuever and again try to shift up but again it will change its mind and go back to the same gear it was already in. By this time we are usually at the top of the hill and the car no longer feels like it's stressed and will drive on and will soon change to the higher gear and no more problem.

When it's climbing the hill and it's starting to feel like it's needing to shift but can't, then if I lay off the gas the car will just keep on climbing in 2nd gear and reaches the top eventually. At the top it relaxes so to speak and comfortably drives on and will soon shift to a higher gear and the problem is over.

I'm sorry I'm not very good in these matters. My mechanic is not at all familiar with Previas
and that's why I thought to look here as well in the hope that someone might be knowledgeable about the Previa in this behavior.

My mechanic wants us to leave it overnight so he can hook up his scan tool and see what it's doing for himself with a test drive the first thing in the morning when the engine is still cold
and that's what we will probably do as soon as we can get it in there.

Anyway thanks for all your inputs.

We also have a 2000 Tacoma. I like them both a lot.

mulchguy47

 

thanks for the ideas. I'm not sure if it's not going into overdrive or third gear. I am assuming that when it starts from stop it goes into first gear, then as you drive you can feel a shift into the next gear (2nd gear, I assume). Then as you gain speed in 2nd gear you can feel that it should be shifting but it doesn't but just stays in 2nd geqr. Eventually it does shift to the next gear and the problem is over for this time. (This is what it does on flat ground.)

When it climbs the hill near our house, it will go from 1st to 2nd but then,still climbing the hill, it again will feel like it should be shifting and if you keep giving it more gas it will kind of start to shift but then quickly kind of change its mind and jump back into the same gear it was already in (2nd) but still feel like it wants to change to a higher gear. Somtimes it will repeat that manuever and again try to shift up but again it will change its mind and go back to the same gear it was already in. By this time we are usually at the top of the hill and the car no longer feels like it's stressed and will drive on and will soon change to the higher gear and no more problem.

When it's climbing the hill and it's starting to feel like it's needing to shift but can't, then if I lay off the gas the car will just keep on climbing in 2nd gear and reaches the top eventually. At the top it relaxes so to speak and comfortably drives on and will soon shift to a higher gear and the problem is over.

I'm sorry I'm not very good in these matters. My mechanic is not at all familiar with Previas
and that's why I thought to look here as well in the hope that someone might be knowledgeable about the Previa in this behavior.

My mechanic wants us to leave it overnight so he can hook up his scan tool and see what it's doing for himself with a test drive the first thing in the morning when the engine is still cold
and that's what we will probably do as soon as we can get it in there.

Anyway thanks for all your inputs.

We also have a 2000 Tacoma. I like them both a lot.

mulchguy47

What is the reading on your coolant temp gauge when this happens? If the coolant is too cold, it can cause the symptoms you describe. Has the thermostat been changed as well? If the thermostat is stuck, open (?) it won't allow the coolant to warm up, and will keep the engine in cold mode.

 

Tran's

When was the last time the Filter & Trans Fluid was changed (maintenance)?

 

When was the last time the Filter & Trans Fluid was changed (maintenance)?

Just what I was going to say too. Have the trans fluid flushed since most owners never do it. :ugh3:

 

I wondered if fourth gear was locked out until the engine warmed up. Thanks for the info!

 

You're welcome and Yes

Thanks for suggestions.

Our Previa is now at 234,000 miles.
We bought it used at 120,000 miles in 2004.

Transmission fluid has been changed 4 times since we bought it but I don't think the transmission filter has ever been changed at any one of these times.

Engine coolant tmperature is always cold when we have this problem. Once the engine warms up, everything works fine.

mulchguy47

You're welcome

 

Thanks for suggestions

Thanks for suggestions.

Our Previa is now at 234,000 miles.
We bought it used at 120,000 miles in 2004.

Transmission fluid has been changed 4 times since we bought it but I don't think the transmission filter has ever been changed at any one of these times.

Engine coolant tmperature is always cold when we have this problem. Once the engine warms up, everything works fine.

mulchguy47